Surgical instrument and method of positioning an acetabular prosthetic component

ABSTRACT

An orthopaedic surgical instrument for positioning an acetabular prosthetic component in a patient&#39;s surgically-prepared acetabulum includes a surgical tool configured to be coupled to the acetabular prosthetic component, and a gravity-based position indicator removably coupled to the surgical tool. The position indicator includes a first marking indicating a first position of the acetabular prosthetic component, and a second marking indicating a second position.

This application is a divisional application and claims priority to U.S.patent application Ser. No. 15/175,075, which was filed on Jun. 7 2016,and which is a divisional application that claims priority to U.S.patent application Ser. No. 13/434,154, now U.S. Pat. No. 9,358,130,which was filed on Mar. 29, 2012, the entirety of each of which isexpressly incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to orthopaedic surgicalinstruments and, more particularly, to surgical instruments used totrial and install an acetabular prosthetic component.

BACKGROUND

Joint arthroplasty is a well-known surgical procedure by which adiseased and/or damaged natural joint is replaced by a prosthetic joint.For example, in a hip arthroplasty surgical procedure, a patient'snatural hip ball and socket joint is partially or totally replaced by aprosthetic hip joint. A typical prosthetic hip joint includes anacetabular prosthetic component and a femoral head prosthetic component.An acetabular prosthetic component generally includes an outer shellconfigured to engage the acetabulum of the patient and an inner bearingor liner coupled to the shell and configured to engage the femoral head.The femoral head prosthetic component and inner liner of the acetabularcomponent form a ball and socket joint that approximates the natural hipjoint.

To facilitate the replacement of the natural joint with a prosthetic hipjoint, orthopaedic surgeons may use a variety of orthopaedic surgicalinstruments such as, for example, reamers, drill guides, drills,positioners, and/or other surgical instruments.

SUMMARY

According to one aspect of the disclosure, an orthopaedic surgicalinstrument for positioning an acetabular prosthetic component in apatient's surgically-prepared acetabulum is disclosed. The orthopaedicsurgical instrument includes a shaft having a first end configured to becoupled to the acetabular prosthetic component, a handle attached to theshaft at a second end opposite the first end, and a bubble indicatorattached to the shaft between the first end and the second end. Thebubble indicator has a face and a plurality of markings defined on theface. The plurality of markings include a first marking indicating afirst abduction angle, and a second marking indicating a secondabduction angle and an anteversion angle of the acetabular prostheticcomponent.

In some embodiments, the second abduction angle may be less than thefirst abduction angle. In some embodiments, the first abduction anglemay be approximately 45 degrees. Additionally, in some embodiments, thesecond abduction angle may be approximately 40 degrees. In someembodiments, the anteversion angle may be equal to approximately 15degrees of rotation about a transverse axis extending through thepatient.

In some embodiments, the bubble indicator may be detachable from theshaft. In some embodiments, the first marking and the second marking maybe customized patient-specific markings.

In some embodiments, the face may be circular and have a center point.The first marking may be located approximately at the center point ofthe face. Additionally, in some embodiments, the second marking may beoffset from the center point of the face.

In some embodiments, the first marking may include a graphical indicatorand a numerical indicator of the first abduction angle.

According to another aspect, the orthopaedic surgical instrumentincludes a surgical tool configured to be coupled to the acetabularprosthetic component, and a gravity-based position indicator removablycoupled to the surgical tool. The position indicator includes a firstmarking indicating a first position of the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum, and a secondmarking indicating a second position of the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum.

In some embodiments, the first marking may indicate a first abductionangle, and the second marking may indicate a second abduction angle. Thesecond abduction angle may be different from the first abduction angle.In some embodiments, the surgical tool may have an aperture definedtherein, and the position indicator may include a rod shaped to matchthe aperture of the surgical tool such that the position indicator iscoupled to the surgical tool in a single predetermined orientation.

In some embodiments, the surgical tool may have a plurality of externalthreads formed on one end. The plurality of external threads maycorrespond to a plurality of internal threads of the acetabularprosthetic component to permit the surgical tool to be threadinglyengaged with the acetabular prosthetic component.

According to another aspect, a method of positioning an acetabularprosthetic component in a patient's surgically-prepared acetabulum isdisclosed. The method includes rotating the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum until a bubbleof a bubble indicator is substantially aligned with a first marking. Thefirst marking indicates a first position of the acetabular prostheticcomponent. The method also includes rotating the acetabular prostheticcomponent anteriorly until the bubble is substantially aligned with asecond marking. The second marking indicates a second position of theacetabular prosthetic component.

In some embodiments, the acetabular prosthetic component may be at afirst abduction angle in the first position, and the acetabularprosthetic component may be at a second abduction angle in the secondposition. The second abduction angle may be less than the firstabduction angle.

In some embodiments, the first abduction angle may be approximately 45degrees. Additionally, in some embodiments, the second abduction anglemay be approximately 40 degrees. In some embodiments, rotating theacetabular prosthetic component anteriorly may include rotating theacetabular prosthetic cup approximately 15 degrees about a transverseaxis extending through the patient.

In some embodiments, the method may further include rotating theacetabular prosthetic component in the patient's surgically-preparedacetabulum until the bubble is substantially aligned with a thirdmarking. The third marking may correspond to a third position of theacetabular prosthetic cup.

In some embodiments, the method may further include selecting the bubbleindicator from a plurality of bubble indicators, attaching the bubbleindicator to a surgical tool, and threading the acetabular prostheticcomponent onto the surgical tool.

Additionally, in some embodiments, rotating the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum until thebubble of the bubble indicator is substantially aligned with a firstmarking may include aligning a graphical indicator of the first markingwith the bubble of the bubble indicator.

In some embodiments, the method may also include positioning the bubbleindicator in a coronal plane defined by the patient's body such that thefirst marking is aligned with the coronal plane. Rotating the acetabularprosthetic component in the patient's surgically-prepared acetabulum mayinclude maintaining alignment between the first marking and the coronalplane.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the following figures,in which:

FIG. 1 is an exploded perspective view of an orthopaedic surgicalinstrument assembly and an acetabular prosthetic component;

FIG. 2 is a perspective view of one embodiment of a position indicatorof the orthopaedic surgical instrument assembly of FIG. 1;

FIG. 3 is a front elevation view of the position indicator of FIG. 2;

FIG. 4 is a perspective view of the orthopaedic surgical instrumentassembly of FIG. 1;

FIG. 5 is a perspective view of the orthopaedic surgical instrumentassembly secured to the acetabular prosthetic component, which ispositioned in a patient's surgically-prepared acetabulum;

FIG. 6 is an elevation view of the orthopaedic surgical instrumentassembly and the acetabular prosthetic component in a predeterminedposition;

FIG. 7 is a front elevation view of the position indicator of theorthopaedic surgical instrument assembly when the orthopaedic surgicalinstrument assembly is positioned in the predetermined position of FIG.6;

FIG. 8 is a plan view of the orthopaedic surgical instrument assemblyand the acetabular prosthetic component in another predeterminedposition;

FIG. 9 is a front elevation view of the position indicator of theorthopaedic surgical instrument assembly when the orthopaedic surgicalinstrument assembly is positioned in the predetermined position of FIG.8;

FIG. 10 is an elevation view of the orthopaedic surgical instrumentassembly and the acetabular prosthetic component in the predeterminedposition of FIG. 8;

FIG. 11 is a perspective view of another embodiment of a positionindicator of the orthopaedic surgical instrument assembly of FIG. 1; and

FIG. 12 is a perspective view of another embodiment of a positionindicator of the orthopaedic surgical instrument assembly of FIG. 1.

DETAILED DESCRIPTION OF THE DRAWINGS

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

Terms representing anatomical references, such as anterior, posterior,medial, lateral, superior, inferior, etcetera, may be used throughoutthe specification in reference to the orthopaedic implants and surgicalinstruments described herein as well as in reference to the patient'snatural anatomy. Such terms have well-understood meanings in both thestudy of anatomy and the field of orthopaedics. Use of such anatomicalreference terms in the written description and claims is intended to beconsistent with their well-understood meanings unless noted otherwise.

Referring to FIG. 1, an acetabular prosthetic component 10 and anorthopaedic surgical instrument assembly 12 (hereinafter assembly 12)are shown. The assembly 12 may be used during a hip arthroplastysurgical procedure to trial and install the acetabular prostheticcomponent 10 in a patient's bone. It should be appreciated, however,that although the assembly 12 is described below in regard to theperformance of a hip arthroplasty surgical procedure, certain conceptsassociated with the assembly 12 may be utilized in replacementprocedures of numerous other joints throughout the body. In other words,one or more of the elements of the assembly 12 may be incorporated intosurgical instruments used in, for example, knee, spinal, shoulder, orother replacement procedures.

The acetabular prosthetic component 10 includes an acetabular shellcomponent 14 configured to be implanted within a surgically-preparedacetabulum 16 (see FIG. 5) of a patient. The acetabular shell component14 includes an outer surface 20 having a convex shape that ishemispherical or partially spherical. The acetabular shell component 14also includes an inner surface 22 having a concave shape that ispartially spherical in shape. The inner surface 22 defines a cavity 24in the acetabular shell component 14 that is sized to receive a metallicor polymeric insert.

The acetabular shell component 14 has an opening 26 defined in the outersurface 20, and an inner wall 28 extends inwardly from the opening 26 toan opening 30 defined in the inner surface 22. The inner wall 28 definesa passageway 32 through the acetabular shell component 14. As shown inFIG. 1, the inner wall 28 has a plurality of internal threads 34 definedthereon.

The orthopaedic surgical instrument assembly 12 includes a surgical tool40 and a position indicator 42. In the illustrative embodiment, thesurgical tool 40 is an impaction tool. It should be appreciated that inother embodiments the surgical tool 40 may be a positioning tool orother surgical device configured to be secured to the acetabularprosthetic component 10. The surgical tool 40 has a shaft 44 thatincludes a plurality of external threads 46 corresponding to the threads34 of the acetabular shell component 14. As shown in FIG. 1, theexternal threads 46 are defined at an end 48 of the shaft 44 such thatthe acetabular shell component 14 may be threaded onto the end 48 of theshaft 44, thereby coupling the acetabular shell component 14 to thesurgical tool 40 for trialing or implantation.

The shaft 44 of the surgical tool 40 has a cylindrical body 50 thatextends from the end 48 to an end 52 and defines a longitudinal axis 54.The surgical tool 40 includes a handle 56 that is coupled to the end 52of the shaft 44. As shown in FIG. 1, the handle 56 includes a handlebody 58, and, in the illustrative embodiment, the shaft 44 is operableto pivot about the longitudinal axis 54 relative to the handle body 58.

The surgical tool 40 also includes a locking mechanism 60 configured toprevent the shaft 44 from pivoting about the axis 54. The lockingmechanism 60 is positioned in the handle body 58 and includes a button62 positioned in an opening 64 defined in the handle body 58. A user mayoperate the button 62 to release the locking mechanism 60 such that theshaft 44 may be pivoted about the axis 54. It should be appreciated thatin other embodiments the locking mechanism 60 may include a switch, tab,or other user-operated device to release and lock the shaft 44 relativeto the handle body 58. It should be appreciated that in otherembodiments the shaft 44 and the handle 56 may be formed as a singlemonolithic component such that the shaft 44 does not pivot or rotaterelative to the handle 56.

As shown in FIG. 1, the handle 56 of the surgical tool 40 also includesa grip 66 secured to the handle body 58. The grip 66 includes a knurledouter surface 68 that is sized to receive the hand of a surgeon or otheruser. It should be appreciated that in other embodiments the outersurface may be substantially smooth or include a number of ribs tosupport the hand of a user.

The handle body 58 of the surgical tool 40 also includes a platform 70configured to receive the position indicator 42. The platform 70 has anupper surface 72, and an opening 74 is defined in the upper surface 72.As shown in FIG. 1, the opening 74 is defined by a substantiallystraight edge 76 and a curved or rounded edge 78. A substantially planarinner wall 80 slopes inwardly from the edge 76. The inner wall 80cooperates with a curved inner wall 82 that slopes inwardly from therounded edge 78 to define an aperture 84 in the handle body 58. Asdescribed in greater detail below, the aperture 84 is sized and shapedto receive a rod 86 of the position indicator 42.

Referring now to FIG. 2, the position indicator 42 of the assembly 12has a longitudinal axis 88 that extends a housing 90 and the rod 86,which is secured to a lower end 92 of the housing 90. The rod 86includes a cantilevered support arm 94 that extends from the lower end92 of the housing 90. The support arm 94 has a curved outer surface 96that is shaped to match the curved inner wall 82 of the handle body 58.The support arm 94 has a substantially planar surface 98 that ispositioned opposite the outer surface 96.

The rod 86 of the position indicator 42 also includes a cantileveredspring arm 100 that extends from the lower end 92 of the housing 90. Thespring arm 100 includes a substantially planar surface 102 that facesthe surface 98 of the support arm 94. The spring arm 100 also includesanother substantially planar surface 104, which is positioned oppositethe surface 102. The surface 104 of the spring arm 100 is shaped tomatch the substantially planar inner wall 80 of the handle body 58.

In the illustrative embodiment, the spring arm 100 of the rod 86 isconfigured to flex and move relative to the support arm 94 between anuncompressed position and a compressed position. As shown in FIG. 2, thetip 106 of the spring arm 100 and the tip 108 of the support arm 94define an uncompressed thickness 110 of the rod 86. The uncompressedthickness 110 is greater than the size of the opening 74 of the handlebody 58.

To attach the position indicator 42 to the surgical tool 40, the rod 86is advanced into the aperture 84 defined in the handle body 58. The arms94, 100 of the rod 86 are advanced into contact with the inner walls 82,80, respectively, of the handle body 58 that define the aperture 84.When the spring arm 100 engages the inner wall 80, the spring arm 100moves relative to the support arm 94 from the uncompressed position tothe compressed position, thereby permitting the rod 86 to advance alongthe inner walls 82, 80 of the handle body 58. When the positionindicator 42 is attached to the surgical tool 40 as shown in FIG. 4, thespring arm 100 acts as a biasing element to prevent inadvertentdetachment of the position indicator 42 from the handle body 58.

The arms 94, 100 of the rod 86 are keyed to match the shape of theaperture 84 such that the position indicator 42 is located in a singlepredetermined orientation relative to the surgical tool 40. It should beappreciated that in other embodiments the rod of the position indicator42 may be a single shaft that is similarly keyed to match the structureof the aperture of the handle body 58. Additionally, in otherembodiments, the aperture may be cylindrical and the rod may have asingle cylindrical shaft sized to be received in the aperture. In otherembodiments, the position indicator and the surgical tool may beconfigured such that the position indicator is permitted to rotate aboutits axis 88 between multiple predetermined positions.

It should also be appreciated that in other embodiments the assembly 12may include other locking mechanisms, such as, for example, latches,pins, threaded fasteners, and other retention devices to secure theposition indicator to the handle body. It should also be appreciatedthat in other embodiments the position indicator 42 may be fixed to thehandle body 58 such that the position indicator 42 cannot be detachedfrom the handle body 58 during normal use.

Referring now to FIG. 3, the position indicator 42 of the assembly 12includes a housing 90 having a gravity-based indicator 112 securedthereto. As used herein, a “gravity-based indicator” is a sensor thatindicates position based on gravity. In the illustrative embodiment, thegravity-based indicator 112 is a bubble indicator 114. In otherembodiments, the gravity-based indicator 112 may be a tilt sensor,including, for example, an enclosed shallow dish filled with fluid. Aball bearing is positioned in the shallow dish and is configured to movebased on the angle or tilt of the shallow dish.

The bubble indicator 114 of the position indicator 42 includes a vial116 that defines a chamber 118 filled with a fluid such as, for example,isopropyl alcohol. In the illustrative embodiment, the vial 116 definesa dome-shaped chamber 118. A bubble 120 is trapped within the chamber118. Gravity and the physical difference between the gas of the bubble120 and the fluid in the chamber 118 control the function of the bubbleindicator 114, with the bubble 120 floating toward the side of the vial116 that constitutes the high side of the vial 116.

The vial 116 of the bubble indicator 114 has a face plate 122 that issubstantially transparent. In that way, a user may look through the faceplate 122 to determine the position of the bubble 120. As shown in FIG.3, the bubble indicator 114 has a plurality of markings 124 etched intoan outer surface 126 of the face plate 122. Each of the markings 124indicates a predetermined position of the acetabular prostheticcomponent 10 within the patient's surgically-prepared acetabulum 16.

In the illustrative embodiment, the markings 124 of the bubble indicator114 include a plurality of graphical indicators 128 that correspond tothe plurality of predetermined positions of the acetabular prostheticcomponent 10. The markings 124 also include a plurality of numericalindicators 130 that are associated with the graphical indicators 128. Asshown in FIG. 3, the graphical indicators 128 include rings 132, 134,136, and the bubble 120 is configured to align with each of the rings132, 134, 136 based on the position of the acetabular prostheticcomponent 10 within the patient's surgically-prepared acetabulum 16, asdescribed in greater detail below. The markings 124 further include sideindicators 138, which associate the graphical indicators 128 and thenumerical indicators 130 with a particular side of a patient's body(i.e., right or left).

The housing 90 of the position indicator 42 is formed from an implantgrade metallic material, such as, for example, aluminum or titanium. Thevial 116 is sealed within the housing 90 such that the positionindicator 42 may be autoclaved for multiple uses. In other embodimentsthe housing 90 may be molded from a polymeric material, such as, forexample, plastic. It should be appreciated that the position indicator42 may be a reusable or disposable surgical instrument.

In use, a surgeon or other user may utilize the assembly 12 to trial andimplant the acetabular prosthetic component 10. To do so, the surgicaltool 40 is assembled with the position indicator 42 and the acetabularprosthetic component 10, as shown in FIG. 4. As shown in FIGS. 5 and 6,the surgical tool 40 may be used to position the acetabular prostheticcomponent 10 within the patient's acetabulum 16 at an initialpredetermined position at a predetermined abduction angle. As shown inFIGS. 8 and 10, the surgical tool 40 may be used to position theacetabular prosthetic component 10 within the patient's acetabulum 16 atanother predetermined position at another predetermined abduction angle.

As shown in FIG. 4, the position indicator 42 may be attached to thetool 40. As described above, the rod 86 of the position indicator 42 isadvanced into the aperture 84 defined in the handle body 58. The arms94, 100 of the rod 86 are advanced into contact with the inner walls 82,80, respectively, of the handle body 58 that define the aperture 84.When the spring arm 100 engages the inner wall 80, the spring arm 100moves relative to the support arm 94 from the uncompressed position tothe compressed position, thereby permitting the rod 86 to advance alongthe inner walls 82, 80 of the handle body 58 such that the positionindicator 42 is assembled with the tool 40.

The acetabular prosthetic component 10 may also be attached to the tool40. To do so, the passageway 32 defined in the acetabular shellcomponent 14 is aligned with the shaft 44 of the tool 40. The acetabularshell component 14 may be advanced into contact with the end 48 of theshaft 44 such that the threads 34 of the acetabular shell component 14engage the threads 46 of the shaft 44. One of the tool 40 and theacetabular shell component 14 may then be rotated relative to the othercomponent to thread the acetabular shell component 14 onto the end 48 ofthe shaft 44, thereby securing the acetabular shell component 14 to thesurgical tool 40.

With the acetabular shell component 14 secured to the surgical tool 40,the acetabular shell component 14 may be advanced into the patient'ssurgically-prepared acetabulum 16, as shown in FIG. 5. To do so, thepatient may be placed into a right or left lateral decubitus positionsuch that the patient's surgically-prepared acetabulum 16 faces upward.As shown in FIG. 6, in the lateral decubitus position, the patient'sbody 140 defines a transverse axis 142 that extends parallel to theground, as indicated by an imaginary axis 144. The patient's body 140also defines a coronal plane 146, and a coronal axis 148 extendsorthogonally to the coronal plane 146 and the transverse axis 142.

A user may utilize the tool 40 to rotate the acetabular shell component14 to an initial predetermined position within the patient'ssurgically-prepared acetabulum 16. As shown in FIG. 6, the surgical tool40 is located in the coronal plane 146 defined by the patient's body 140such that the longitudinal axis 54 of the surgical tool 40 and thelongitudinal axis 88 of the position indicator 42 are located in thecoronal plane 146. While maintaining the surgical tool 40 in the coronalplane 146, a user may rotate the surgical tool 40 about the coronal axis148 to move the acetabular shell component 14. As the surgical tool 40is pivoted about the axis 148, the bubble 120 is moved within the vial116 of the position indicator 42.

As shown in FIG. 7, the acetabular shell component 14 is located in theinitial predetermined position when the bubble 120 is aligned with thering 132 defined on the face plate 122 of the vial 116. The longitudinalaxis 88 of the position indicator 42 extends outwardly through thecenter 156 of the face plate 122, and the ring 132 is aligned with thecenter 156. In the initial predetermined position, the coronal plane 146is aligned with the longitudinal axis 88 and bisects the ring 132, asshown in FIG. 7.

As shown in FIG. 6, an angle α is defined between the longitudinal axis54 of the surgical tool 40 and the transverse axis 142 at thepredetermined position corresponding to the ring 132. In theillustrative embodiment, the angle α is equal to a predetermined amountof rotation about the coronal axis 148 and a predetermined abductionangle. The face plate 122 of the position indicator 42 includes anumerical indicator 150 that indicates to the user the magnitude of theangle α, as shown in FIG. 7. In the illustrative embodiment, the angle αhas a magnitude of 45 degrees.

As shown in FIG. 8, the user may utilize the tool 40 to rotate theacetabular shell component 14 from the initial predetermined position toanother predetermined position within the patient's surgically-preparedacetabulum 16. To do so, a user may rotate the surgical tool 40 aboutthe transverse axis 142 and/or the coronal axis 148 to move theacetabular shell component 14. In the illustrative embodiment, the userrotates the surgical tool 40 about the transverse axis 142 such that thesurgical tool 40 is angled out of the coronal plane 146. As shown inFIG. 8, the surgical tool 40 is rotated anteriorly relative to thecoronal plane 146. The user also rotates the surgical tool 40 relativeto the coronal axis 148.

As the surgical tool 40 is pivoted about the axes 142, 148, the bubble120 is moved within the vial 116 of the position indicator 42. As shownin FIG. 9, the acetabular shell component 14 is located in the secondpredetermined position when the bubble 120 is aligned with the ring 134defined on the face plate 122 of the vial 116.

As shown in FIG. 8, an angle β is defined between the longitudinal axis54 of the surgical tool 40 and the coronal plane 146 at thepredetermined position corresponding to the ring 134. In theillustrative embodiment, the angle β is equal to a predetermined amountof rotation about the transverse axis 142 and a predeterminedanteversion angle. As shown in FIG. 10, an angle ϕ is defined betweenthe longitudinal axis 54 of the surgical tool 40 and the transverse axis142 at the predetermined position corresponding to the ring 134. In theillustrative embodiment, the angle ϕ is equal to a predetermined amountof rotation about the coronal axis and a predetermined abduction angle.The face plate 122 of the position indicator 42 includes numericalindicators 152, 154 that indicate to the user the magnitudes of theangles β, ϕ, as shown in FIG. 9. In the illustrative embodiment, theangle β has a magnitude of 15 degrees the angle ϕ has a magnitude of 40degrees.

It should be appreciated that the magnitudes of the angles α, β, ϕ mayvary according to anatomy of a particular patient. For example, themagnitude of the angles α, ϕ may be between 35 degrees and 50 degrees,or, for example, the magnitude of the angle β may be between 15 and 30degrees. It should be appreciated that different position indicatorswith markings indicating different predetermined positions may be usedduring the installation process. In other embodiments, the positionindicator may be a customized, patient-specific position indicator. Asused herein, the term “customized, patient-specific” refers to astructure that has been created for use with a single patient. Forexample, the position indicator may include markings corresponding tocustom, predetermined positions of the acetabular prosthetic componentthat are unique to a particular patient. In other embodiments, themarkings of the position indicator may be based on surgeon-preferences.

Additionally, while the assembly 12 is used with the acetabularprosthetic component 10 in the procedure outlined above, the assembly 12may also be used with an acetabular prosthetic trial component. Whenattached to a trial component, the user may use the assembly 12 todetermine the type, configuration, and installed position of theacetabular prosthetic component that is to be implanted. It should beappreciated that different position indicators with markings indicatingdifferent predetermined positions may be used during the trialingprocess to determine the installed position of the acetabular prostheticcomponent.

Referring now to FIG. 11, another embodiment of a position indicator(hereinafter position indicator 242) is shown. Some features of theembodiment illustrated in FIG. 11 are substantially similar to thosediscussed above in reference to the embodiment of FIGS. 1-10. Suchfeatures are designated in FIG. 11 with the same reference numbers asthose used in FIGS. 1-10. The position indicator 242, like the positionindicator 42, is configured to be attached to the surgical tool 40.

The position indicator 242 includes a housing 90 and a rod (not shown)sized to be received in the aperture 84 of the handle body 58. Theposition indicator 242 includes a bubble indicator 244 having a vial 246that defines a dome-shaped chamber 118 filled with a fluid such as, forexample, isopropyl alcohol. Like the vial 116 of the position indicator42, a bubble 120 is trapped within the chamber 118. Gravity and thephysical difference between the gas of the bubble 120 and the fluid inthe chamber 118 control the function of the bubble indicator 244, withthe bubble 120 floating toward the side of the vial 246 that constitutesthe high side of the vial 246.

The vial 246 of the bubble indicator 244 has a face plate 248 that issubstantially transparent. In that way, a user may look through the faceplate 248 to determine the position of the bubble 120. As shown in FIG.11, the bubble indicator 244 has a plurality of markings 250 etched intoan outer surface 252 of the face plate 248. Each of the markings 250corresponds to a predetermined position of the acetabular prostheticcomponent 10 within the patient's surgically-prepared acetabulum 16.

In the illustrative embodiment, the markings 250 of the bubble indicator244 include a plurality of graphical indicators 254 that correspond to aplurality of predetermined positions of the acetabular prostheticcomponent 10. As shown in FIG. 11, the graphical indicators 254 includerings 132, 134, 136, which correspond to the angles α, β, ϕ describedabove in reference to the embodiment of FIGS. 1-10. The graphicalindicators 254 of the bubble indicator 244 also include a plurality ofadditional arcs 256 that correspond to additional predeterminedpositions of the acetabular prosthetic component 10. In the illustrativeembodiment, the markings 254 also include a plurality of numericalindicators 258 that are associated with the graphical indicators 254 andindicate to the user the magnitude of the angles α, β, ϕ at variouspredetermined positions.

In use, the position indicator 242 may be used by a surgeon to determinethe proper position of the acetabular prosthetic component 10 from theplurality of predetermined positions indicated by the markings 250. Forexample, when used with an acetabular prosthetic trial component, theuser may use the position indicator 242 to determine the type,configuration, and installed position of the acetabular prostheticcomponent 10 by moving the acetabular prosthetic component 10 betweenmultiple predetermined positions.

Referring now to FIG. 12, another embodiment of a position indicator(hereinafter indicator 342) is shown attached to the surgical tool 40.Some features of the embodiment illustrated in FIG. 12 are substantiallysimilar to those discussed above in reference to the embodiment of FIGS.1-10. Such features are designated in FIG. 12 with the same referencenumbers as those used in FIGS. 1-10. The position indicator 242, likethe position indicator 42, is configured to be attached to the surgicaltool 40.

The position indicator 342 includes a housing 344 and a rod 86 sized tobe received in the aperture 84 of the handle body 58. The housing 344includes an arm 346 that extends parallel to the longitudinal axis 54 ofsurgical tool 40 and a base 348 that extends orthogonal to the arm 346.As shown in FIG. 12, the position indicator 342 includes a bubbleindicator 350 secured to the arm 346 and another bubble indicator 352secured to the base 348.

The bubble indicator 350 includes an oblong-shaped vial 354 that extendsparallel to the axis 54 of the surgical tool 40. The vial 354 defines achamber 356 filled with a fluid such as, for example, isopropyl alcohol,and a bubble 358 is trapped within the chamber 356. The bubble indicator352 includes an oblong-shaped vial 360 that extends orthogonal to thevial 354. The vial 360 defines a chamber 362 filled with a fluid, and abubble 364 is trapped within the chamber 362. Gravity and the physicaldifference between the gas of the bubbles 358, 364 and the fluid in thechamber 356, 362, respectively, control the function of the bubbleindicators 350, 352, with the bubbles 358, 364 floating toward the highsides of the vials 354, 360.

Each of the bubble indicators 350, 352 includes a face plate 370, 372,respectively. The face plates 370, 372 are substantially transparent. Inthat way, a user may look through the face plates 370, 372 to determinethe respective positions of the bubbles 350, 352. The face plate 370 hasa plurality of markings 374 that indicate a plurality of predeterminedpositions of the acetabular prosthetic component 10 within the patient'ssurgically-prepared acetabulum 16. In the illustrative embodiment, themarkings 374 correspond to predetermined amounts of rotation about thecoronal axis 148 and predetermined abduction angles.

The face plate 372 of the bubble indicator 352 has a plurality ofmarkings 376 that indicate a plurality of predetermined positions of theacetabular prosthetic component 10 within the patient'ssurgically-prepared acetabulum 16. In the illustrative embodiment, themarkings 376 correspond to predetermined amounts of rotation about thetransverse axis 142 and predetermined anteversion angles.

In the illustrative embodiment, the markings 374, 376 of the bubbleindicator 350, 352 include a plurality of graphical indicators 380, 382that correspond to a plurality of predetermined positions of theacetabular prosthetic component 10 within the patient'ssurgically-prepared acetabulum 16. It should be appreciated that inother embodiments the markings 374, 376 may include numerical or sideindicators similar to those described above in regard to FIGS. 1-10.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, such an illustration and descriptionis to be considered as exemplary and not restrictive in character, itbeing understood that only illustrative embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of the disclosure are desired to be protected.

There are a plurality of advantages of the present disclosure arisingfrom the various features of the method, apparatus, and system describedherein. It will be noted that alternative embodiments of the method,apparatus, and system of the present disclosure may not include all ofthe features described yet still benefit from at least some of theadvantages of such features. Those of ordinary skill in the art mayreadily devise their own implementations of the method, apparatus, andsystem that incorporate one or more of the features of the presentinvention and fall within the spirit and scope of the present disclosureas defined by the appended claims.

1. An orthopaedic surgical system, the orthopaedic surgical systemcomprising: an acetabular prosthetic component sized to be positioned ina patient's surgically-prepared acetabulum, and a surgical instrumentcomprising: a surgical tool configured to be coupled to the acetabularprosthetic component, and a gravity-based position indicator removablycoupled to the surgical tool, the position indicator including: (i) afirst marking indicating a first position of the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum, wherein thefirst marking indicates a first abduction angle of the acetabularprosthetic component, and (ii) a second marking indicating a secondposition of the acetabular prosthetic component in the patient'ssurgically-prepared acetabulum, wherein the second marking indicates: asecond abduction angle of the acetabular prosthetic component differentfrom the first abduction angle, and a first anteversion angle of theacetabular prosthetic component.
 2. The orthopaedic surgical system ofclaim 1, wherein: the surgical tool has an aperture defined therein, andthe position indicator includes a rod shaped to match the aperture ofthe surgical tool such that the position indicator is coupleable to thesurgical tool in a single predetermined orientation.
 3. The orthopaedicsurgical system of claim 2, wherein the rod includes a support arm and aspring arm moveable relative to the support arm from (i) an uncompressedposition wherein the position indicator is spaced apart from thesurgical tool to (ii) a compressed position wherein the positionindicator is coupled to the surgical tool.
 4. The orthopaedic surgicalsystem of claim 3, wherein the spring arm is biased toward theuncompressed position to prevent detachment of the position indicatorfrom the surgical tool when the rod of the position indicator ispositioned in the aperture of the surgical tool.
 5. The orthopaedicsurgical system of claim 1, wherein the surgical tool has a plurality ofexternal threads formed on one end, the plurality of external threadscorresponding to a plurality of internal threads of the acetabularprosthetic component to permit the surgical tool to be threadinglyengaged with the acetabular prosthetic component.
 6. The orthopaedicsurgical system of claim 1, wherein the position indicator includes athird marking indicating a third abduction angle of the acetabularprosthetic component.
 7. The orthopaedic surgical system of claim 6,wherein the third marking indicates a second anteversion angle of theacetabular prosthetic component.
 8. The orthopaedic surgical system ofclaim 6, wherein: the position indicator is bubble indicator having avial with a bubble trapped therein, and the first marking is located atthe center point of the vial.
 9. The orthopaedic surgical system ofclaim 8, wherein the second marking is offset from the center point ofthe vial.
 10. The orthopaedic surgical system of claim 9, wherein athird marking indicating a third abduction angle of the acetabularprosthetic component is offset from the center point of the vialopposite the second marking.
 11. The orthopaedic surgical system ofclaim 1, wherein the first marking is a customized patient-specificmarking.
 12. The orthopaedic surgical instrument system of claim 1,wherein the second marking is a customized patient-specific marking. 13.The orthopaedic surgical instrument system of claim 7, wherein the thirdmarking is a customized patient-specific marking.
 14. An orthopaedicsurgical system for positioning an acetabular prosthetic component in apatient's surgically-prepared acetabulum, the instrument systemcomprising: an acetabular prosthetic component sized to be positioned ina patient's surgically-prepared acetabulum, and a surgical instrumentcomprising: a surgical tool configured to be coupled to the acetabularprosthetic component, and a gravity-based position indicator removablycoupled to the surgical tool, the position indicator including: (i) afirst marking indicating a first position of the acetabular prostheticcomponent in the patient's surgically-prepared acetabulum, wherein thefirst marking indicates a first abduction angle of the acetabularprosthetic component, and (ii) a second marking indicating a secondposition of the acetabular prosthetic component in the patient'ssurgically-prepared acetabulum, wherein the second marking indicates asecond abduction angle of the acetabular prosthetic component differentfrom the first abduction angle.
 15. The orthopaedic surgical system ofclaim 13, wherein the first marking is a customized patient-specificmarking.
 16. The orthopaedic surgical system of claim 13, wherein thesecond marking a customized patient-specific marking.
 17. Theorthopaedic surgical system of claim 13 wherein: the surgical tool hasan aperture defined therein, and the position indicator includes a rodshaped to match the aperture of the surgical tool such that the positionindicator is coupleable to the surgical tool in a single predeterminedorientation.
 18. The orthopaedic surgical system of claim 17, whereinthe rod includes a support arm and a spring arm moveable relative to thesupport arm from (i) an uncompressed position wherein the positionindicator is spaced apart from the surgical tool to (ii) a compressedposition wherein the position indicator is coupled to the surgical tool.19. The orthopaedic surgical system of claim 18, wherein the spring armis biased toward the uncompressed position to prevent detachment of theposition indicator from the surgical tool when the rod of the positionindicator is positioned in the aperture of the surgical tool.
 20. Theorthopaedic surgical system of claim 14, wherein the position indicatorincludes a third marking indicating a third abduction angle of theacetabular prosthetic component.